The present invention relates to an optical recording and reproducing apparatus and, more particularly, to an optical recording and reproducing apparatus which can prevent a tracking error by correcting the position of a spindle motor which rotates a turntable.
The optical recording and reproducing apparatus is for reproducing the information recorded in optical recording media (which are referred to as a disk hereinafter) such as a compact disk, digital video disk, and a laser disk. A disk is loaded on the turntable installed in the optical recording and reproducing apparatus and rotates. An optical pickup detects an optical signal from a pit formed in the disk.
FIG. 1 is a perspective view schematically showing a portion of a conventional optical recording and reproducing apparatus. As shown in FIG. 1, an optical recording and reproducing apparatus 10 comprises a deck 11, a turntable 12 on which a disk (not shown) is loaded, a spindle motor 13 for rotating the turntable 12, an optical pickup 14 movable in a rectilinear and reciprocating manner on the deck 11, a motor 15 for driving an optical pickup 14, and a screw shaft 16 for converting the rotational movement of the motor 15 into rectilinear movement. The optical pickup 14, having a tooth gear portion (not shown) formed in one side thereof and engaged with the screw shaft 16, moves along guide shafts 17 fixed to the deck 11, according to the rotation of the screw shaft 16.
In the optical recording and reproducing apparatus having the above construction, focusing and tracking are performed in order to make the laser beam, incident on the disk, correctly land on a pit (not shown) formed in a track of the disk. While focusing is performed in a perpendicular direction to the disk, tracking is performed in the radial direction of the disk by a so-called three beam method. Using the three beam method, a tracking error is detected by comparing the light quantity of the main beam incident on the pit with that of the beams respectively incident on both sides of the pit.
Generally, since a tracking error is generated in the case where the machining precision of the parts is low or the assembly of the parts is poor, there were no alternatives but to improve the precision of machining of the parts and to assemble the parts correctly in order to decrease or prevent the tracking error. Therefore, an apparatus for effectively removing the tracking error is not provided when the tracking error occurs. Furthermore, when allowances of the parts are accumulated during assembly, means for compensating for the same is required after completing the assembly of the parts.